Why Women Need To Know Their Blood Group
- Posted on May 5, 2026
- Health
- By Excel Magazine Team
- 19 Views
This article highlights the importance of women knowing their blood group, particularly their rhesus (Rh) status, for safe pregnancy outcomes. Blood groups are classified under the ABO and rhesus systems, with the Rh factor playing a critical role in maternal and fetal health.
If a woman who is Rh negative carries an Rh positive baby, her body may produce antibodies that can attack the baby’s red blood cells, potentially causing serious complications. While this usually does not affect the first pregnancy, risks increase in subsequent pregnancies if sensitization occurs through events like miscarriage, delivery, or certain medical procedures.
The good news is that this condition is preventable. With proper medical care, including a simple injection during and after pregnancy, harmful antibody formation can be avoided. Ultimately, knowing one’s blood group empowers women to protect both their own health and that of their unborn child.
BY DR MICHEAL MBULO OBGYN
Blood groups are determined by antigens on the red blood cells. An antigen is any substance that the immune system recognises as foreign, with the potential to trigger an immune response.
Blood groups
There are two blood group systems: the ABO system and the rhesus system. Many people know their A, B, AB and O blood type but don’t know their rhesus blood type. The rhesus complex is made up of several antigens. A parent contributes one to the offspring. Those who carry the D-antigen are referred to as rhesus D positive and those who don’t carry it are referred to as rhesus D negative.
The Rhesus Factor
The rhesus status is extremely important in reproductive health. This is because the D antigen (Rh positive) is capable of stimulating antibody formation. If a woman is Rh negative and conceives from a man who is Rh positive, the baby born will be Rh positive. This is because where the two blood groups co-exist, the positive group is the one that gets expressed.
The problem occurs when a rhesus negative mother is pregnant with a rhesus positive baby and has been sensitised at some stage. There is a chance of anti-D antibodies developing against the unborn baby’s cells. These antibodies may cross back to the baby and destroy the red blood cells. This may cause mild, moderate or severe disease in the unborn baby.
Triggers
Transfer of these red blood cells to the mother may occur without any obvious predisposing event. However, it is more likely to occur with the disruption of the placental bed and may occur following miscarriage, ectopic pregnancy and invasive uterine procedures such as amniocentesis. It most commonly occurs in labour and during delivery, particularly delivery of the placenta.
Sensitization procedure
An immune response does not always follow transfer of foetal red blood cells to the mother due to a number of factors. In general, two exposures to the Rh antigen are required to produce any significant sensitization, unless the first exposure is massive. This is why the first pregnancy is usually not affected.
Medical Intervention
This condition is preventable if you know your Rh status. A single injection given in pregnancy and delivery or after any potentially sensitizing event would stop the mother’s body from forming those harmful antibodies.
Every woman should know her blood group, and especially her rhesus factor. This could protect her pregnancy and subsequently her unborn child.
